Photocoupler

It counts the signals of internal components X, Y, M, S, T, C when performing a scan operation. When the number of counts reaches the set value of the counter, the counter contact acts to control the system to complete the corresponding function. The low-speed counter can not only record the switching signal from the input terminal (input relay), but also record the contact signals of other components inside the plc.

The internal counters are classified according to the frequency at which they are recorded, and can be classified into a low speed counter and a high speed counter.

1) Low speed counter

There are four categories:

16-bit universal up counter: C0∽C99 (100 points); set value range is K1∽K32767

16-bit power-off keep increment counter: C100∽C199 (100 points); setting interval is K1∽K32767

32-bit universal increase/decrease two-way counter: C200∽C219 (20 points); set value range is K-2147483648∽+214783648

32-bit power failure keeps increasing/decreasing bidirectional counter: C220∽C234 (15 points); set value interval is K-2147483648∽+214783648

2) Internal high speed counter (C)

The high-speed counter can only burn the external signal that is fed through the input terminal (input relay), and the frequency of this signal can be as high as several kilohertz. It is also possible to perform a reset operation directly from the input terminal.

The high-speed counter number is 21 points for C235∽C255, which are both 32-bit up/down bi-directional counters. The up-count or down-count is determined by the specified special auxiliary relay or by the specified input terminal. The setting interval is K-2147483648. ∽+214783648.

High-speed counters are generally named in four categories:

1 phase no start / reset terminal: C235∽C240;

1 phase two-way: C246∽C250;

2-phase A-B phase type: C251∽C255;

The convention between the high-speed counter and the input terminal (input relay) is as follows:

Note: U-up counting input; D-down counting input; A-A phase input; B-B phase input; R-reset input; S-start input.

The high-speed counter operates on an interrupt basis, so it is independent of the scan period. The coil of the selected counter should be continuously asserted to indicate that the counter and its associated inputs are continuously active. Other high-speed processing can no longer use its input terminals.

(1) 1-phase high-speed counter C235∽C240

C235∽C240 no start/reset end setting range

-2147483648∽+214783648

C241∽C245 has start/reset end

Description:

When n is incremented, when the count value reaches the set value, the contact moves and remains; when the count is down, the count value is reset.

The counting direction of the n1 phase counter depends on its corresponding flag M8□□□, and □□□ corresponds to the counter number C235∽C245.

(2) 1-phase bidirectional high-speed counter C246∽C250

The 1-phase bidirectional counter has one input for up counting and the other input for down counting. It is necessary to increase or reduce the need to arrange from different inputs instead of using special auxiliary relay conventions. Some counters also have reset and start inputs.

(3) 2-phase A-B phase type high-speed counter: C251∽C255

2-phase 2-input (C251∽C255, 1 or 2, battery backup) can have up to 2 2-phase 32-bit binary up/down counters. It is counted in interrupt mode regardless of the scan period. These counters also have application instructions that perform comparison and output operations independently of logical operations. When the counter component is selected, the corresponding start, reset and input signals can be used. The Phase A and Phase B signals determine whether the counter is up or down.

For example, when the A phase waveform is ON:

B phase input OFF → ON: count up

B phase input ON→OFF: count down